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Manufacturing Process of Slewing Bearings

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Slewing bearings, as crucial components in numerous mechanical equipments, have a complex and intricate manufacturing process. This process involves multiple key steps, and each step significantly impacts the quality and performance of the final product.

What is Slewing Bearing?

The slewing bearing is a large – scale bearing capable of withstanding comprehensive loads. It is used to support and connect mechanical components that need to rotate relative to each other. It typically consists of an inner ring, an outer ring, rolling elements, and a cage. Slewing bearings can simultaneously bear axial forces, radial forces, and overturning moments, and are widely applied in large – scale mechanical equipments such as cranes, excavators, wind turbines, and port machinery. Its function is to enable the rotating parts of the equipment to rotate stably and flexibly, ensuring the normal operation of the equipment, improving its working efficiency and reliability. It is an indispensable key component in many large – scale machines.

Raw Material Procurement and Inspection

The quality of raw materials serves as the foundation for the performance of slewing bearings. The main raw materials include high – quality steel, such as medium – carbon alloy steel, which is used to manufacture key components like inner and outer rings, as well as steel for rolling elements (steel balls or rollers). When purchasing, it is necessary to carefully screen suppliers to ensure that the materials meet national standards and design requirements. After the arrival of the goods, conduct a comprehensive inspection of the raw materials. Use spectral analysis to detect chemical components, evaluate mechanical properties through hardness tests and tensile tests, and check for internal and surface defects using ultrasonic flaw detection and magnetic particle flaw detection. Only raw materials with qualified indicators can enter the production process.

Part Machining of Slewing Bearings

Inner and Outer Ring Machining

Firstly, cut the steel to obtain blanks of appropriate sizes. In the rough turning process, remove most of the allowance, leaving a machining allowance of 0.5 – 1 mm for subsequent finish machining to improve processing efficiency. Finish turning ensures the dimensional accuracy and surface roughness of the inner and outer rings. The dimensional tolerance of the raceway part is controlled within ±0.01 mm, and the surface roughness reaches Ra0.8 – Ra1.6μm. In the milling process, machine structures such as mounting holes and keyways to ensure position accuracy. After the processing is completed, measure the dimensional accuracy again to ensure compliance with the design drawings.

Rolling Element Machining

If steel balls are used, process the steel into spherical blanks, and through processes such as rough grinding, fine grinding, and lapping, gradually improve the dimensional accuracy and surface quality of the steel balls, and control the roundness error within a very small range. The machining of rollers includes turning the outer circle, grinding, and lapping to ensure the cylindricity and surface roughness of the rollers and ensure smooth rolling within the raceway.

Cage Machining

Manufacture the cage by stamping, injection molding, or machining according to design requirements. Stamped cages are suitable for mass production with high efficiency; injection – molded cages have low costs and light weights; machined cages have high precision. After processing, check the dimensional accuracy, structural integrity, and surface quality of the cage to ensure that it can evenly separate the rolling elements and reduce friction and wear between the rolling elements.

Heat Treatment of Slewing Bearings

Quenching and Tempering

Inner rings, outer rings, and rolling elements need to undergo heat treatment after machining. Quenching can improve the hardness and strength of the material. Heat the parts to an appropriate temperature, hold for a certain period of time, and then cool rapidly. Tempering relieves the internal stress generated during quenching and adjusts hardness and toughness. Heat the quenched parts to a range lower than the quenching temperature, hold, and then cool. Through appropriate quenching and tempering processes, the comprehensive mechanical properties of the parts reach the optimal state.

Surface Treatment

To improve the wear resistance, corrosion resistance, and fatigue life of slewing bearings, surface treatment is often carried out. For example, use chemical heat treatment methods such as carburizing and nitriding to form a high – hardness hardened layer on the surface of the parts; or perform surface coating treatments such as electroplating and spraying to cover a protective film on the surface of the parts.

Assembly of Slewing Bearings

Cleaning and Inspection

Before assembly, thoroughly clean all parts to remove impurities such as oil stains and iron filings remaining during the machining process. After cleaning, check the dimensional accuracy, surface quality, and appearance of the parts again to ensure there are no defects or damages.

Assembly Process

First, fix the inner ring on the assembly platform, install the cage, and then install the rolling elements between the cage and the inner ring according to the specified quantity and interval. When installing the outer ring, ensure the fitting accuracy between the outer ring, the inner ring, and the rolling elements, and control the clearance within a reasonable range. If the clearance is too large, it will lead to a decrease in rotational accuracy and an increase in vibration; if the clearance is too small, it will increase friction and wear, and may even cause parts to seize. During the assembly process, use special tools and equipment to ensure assembly accuracy.

Pre – tensioning and Adjustment

Some slewing bearings need to be pre – tensioned. By applying a certain axial or radial force, the clearance is eliminated to improve rotational accuracy and rigidity. After pre – tensioning, test and adjust the rotational flexibility, radial and axial run – out, and other performances of the slewing bearing to ensure compliance with design requirements.

Quality Inspection of Slewing Bearings

Appearance Inspection

Inspect the appearance of the slewing bearing to ensure that there are no defects such as cracks, blowholes, and pores on the surface, and that the paint coating is uniform and free from peeling.

Dimensional Accuracy Detection

Use measuring tools to detect the diameters, widths, raceway sizes of the inner and outer rings, as well as the positions and sizes of the mounting holes, etc., to ensure compliance with the tolerance requirements of the design drawings.

Performance Testing

Carry out rotational flexibility tests to check whether the rotation process is smooth and free from jamming; measure radial and axial run – out to evaluate rotational accuracy; conduct loading tests to detect the bearing capacity and fatigue life of the slewing bearing, ensuring reliable performance in actual use.

Prices of Slewing Bearings

There are many factors affecting the prices of slewing bearings. Firstly, raw materials play a significant role. High – quality steel has a high cost, and products made from it have excellent performance and long service life, thus commanding a high price. Secondly, slewing bearings with complex manufacturing processes and high – precision requirements require advanced equipment and strict quality control, which also leads to an increase in price. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price will be.

Suppliers of Slewing Bearings

The products of Ldb bearing company cover a wide range. Whether they are standard – sized or non – standard slewing bearings, the company can produce them with high quality to meet the diverse needs of different customers. Its products are widely used in multiple fields, demonstrating its strong capabilities.

Applications of Slewing bearings in the Forestry Industry

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In the forestry sector, slewing bearings play a significant role in various processes, from forest resource exploration and tree harvesting to wood processing. They provide crucial support for the efficient operation of forestry machinery, greatly enhancing the efficiency and quality of forestry production.

What is Slewing bearing?

The slewing bearing, also known as a turntable bearing, is a mechanical component that enables relative slewing motion between parts. It typically consists of an inner ring, an outer ring, rolling elements (such as steel balls or rollers), and a cage. Its key function is to simultaneously withstand axial forces, radial forces, and overturning moments. Slewing bearings are widely used in various construction machinery and industrial equipment. For example, cranes rely on them to achieve flexible rotation of the boom, excavators use them to ensure stable rotation of the upper part, and in wind turbines, they support the nacelle to rotate with the wind direction. Thanks to its structure, the slewing bearing can provide a stable slewing foundation for equipment, ensuring its efficient operation.

Applications in Forest Resource Exploration Equipment

During forest resource exploration, some specialized equipment depends on slewing bearings to achieve precise orientation adjustments. For instance, multi – spectral imaging devices mounted on drones or ground exploration vehicles can flexibly change the shooting angle with the help of slewing bearings, enabling comprehensive scanning of large – scale forests. The high – precision characteristics of slewing bearings ensure that the imaging devices remain stable during rotation, obtaining clear and accurate images. This facilitates forestry workers in analyzing the growth status of forest vegetation, the distribution of pests and diseases, and other information. At the same time, in geological exploration radar equipment, the slewing bearing allows the radar antenna to rotate 360 degrees, effectively detecting the underground geological structure and helping to determine the characteristics of forest soil, the groundwater level, etc., providing data support for the rational planning and protection of forests.

Applications in Logging Equipment

Logging Machinery,In modern logging operations, the harvester is one of the core pieces of equipment. The slewing bearing is installed at the joint of the harvester’s boom, allowing the cutting head of the harvester to rotate flexibly to meet the logging requirements of trees in different positions. It can withstand huge loads, including the reaction force generated during tree cutting and the gravity of the boom during extension and rotation. For example, in mountainous forest logging, the harvester needs to quickly adjust the angle of the cutting head through the slewing bearing to cut trees at different inclinations, improving logging efficiency while ensuring the safety of operators.

Log – Hauling Machinery,Log – hauling tractors or cable logging equipment also rely on slewing bearings when collecting felled timber. The boom of the log – hauling tractor can perform multi – angle lifting operations through the slewing bearing, enabling it to flexibly gather timber scattered in the forest. In the cable logging system, the pulley support can rotate freely on the cable by using the slewing bearing, keeping the timber stable during transportation, avoiding collisions and falling, and ensuring the smooth progress of log – hauling operations.

Applications in Wood Processing Equipment

Log Peeling Machines,Log peeling machines are the first – step equipment in wood processing. The slewing bearing is installed on the drum or cutter frame of the peeling machine, enabling the drum to rotate smoothly and drive the log to roll. At the same time, the cutter frame can adjust the angle according to the shape and size of the log. In this way, the peeling cutter can evenly contact the surface of the log, efficiently removing the bark. The stability of the slewing bearing ensures that the axial and radial positions of the log remain relatively fixed during the peeling process, improving the quality and efficiency of peeling and reducing wood waste.

Wood Cutting Equipment,In wood cutting equipment such as band saws and circular saws, the slewing bearing is used to support the rotating shaft of the saw blade and the rotating components of the worktable. It ensures that the saw blade remains stable during high – speed rotation, preventing saw blade wobbling from reducing cutting accuracy. At the same time, the slewing bearing of the worktable allows the wood to be cut at different angles, meeting the processing requirements of various specifications of wood. For example, when producing construction – grade wood, the slewing bearing helps the cutting equipment to accurately cut the log according to the preset size and angle, improving the utilization rate of wood and processing accuracy.

Wood Drying Equipment,In wood drying kilns, the slewing bearing is applied to the rotating system of the drying rack. The drying rack rotates slowly through the slewing bearing, ensuring that the wood is heated evenly during the drying process and avoiding uneven drying. This not only improves the drying quality of the wood but also effectively reduces the deformation and cracking problems caused by improper drying, enhancing the quality and economic value of the wood.

Applications in Forestry Cranes

Forestry cranes are mainly used for the loading, unloading, and lifting of timber. As a key component of the crane, the slewing bearing is installed between the slewing platform and the undercarriage of the crane. It bears the entire weight of the upper structure of the crane and various loads generated during timber lifting. It can achieve 360 – degree rotation of the upper structure of the crane, allowing the boom to flexibly adjust the working radius and angle, facilitating the lifting of timber from transport vehicles and placing it in the designated position. The high – performance of the slewing bearing ensures the stability and reliability of the forestry crane during frequent lifting and slewing operations, improving the efficiency of timber loading and unloading operations and reducing labor intensity.

With the continuous advancement of the forestry modernization process, the applications of slewing bearings in the forestry industry will become more extensive and in – depth. In the future, slewing bearings will develop towards higher precision, greater load – bearing capacity, and more energy – saving and environmental – friendly directions to meet the continuous upgrading requirements of forestry machinery. At the same time, the integration of slewing bearings with intelligent technology will also become a trend, realizing functions such as remote monitoring and fault warning, further enhancing the safety and efficiency of forestry production and providing strong support for the sustainable development of the forestry industry.

Prices of Slewing bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High – quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is also high. Secondly, slewing bearings with complex manufacturing processes and high – precision requirements need advanced equipment and strict quality control, and the price will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and the amount of materials used, and the higher the price will be.

Suppliers of Slewing bearings

Advanced production and testing equipment are the cornerstone of high – quality products. Ldb bearing company is well aware of this and is equipped with nearly 30 sets of various types of equipment, from 3m CNC drilling and milling machines to quenching machines, providing hardware support for precision processing. At the same time, the company has an experienced design and technical team. With their profound professional knowledge and innovative spirit, they continuously optimize product designs and overcome technical problems. For example, during the research and development process, in response to the balance problem between the load – bearing capacity and accuracy of large – scale slewing bearings, the team found an innovative solution after repeated tests and simulation analyses, significantly improving product performance.

How to Select the Appropriate Flange Bearing

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In a mechanical transmission system, flange bearings play a crucial role. They not only support the rotation of the shaft but also ensure the stable operation of the equipment. To select the appropriate flange bearing, it is necessary to comprehensively consider various factors.

What is flanged slewing bearing?

The flanged slewing bearing is a type of slewing bearing. It usually consists of components such as an inner ring, an outer ring, rolling elements (such as steel balls or rollers), and a cage, and is equipped with a flange structure. This flange can be easily fixed to other components of the equipment through connectors like bolts, enabling quick installation and precise positioning. It can simultaneously withstand axial forces, radial forces, and overturning moments, providing stable support for the slewing motion of the equipment. Due to its convenient installation and accurate positioning, it is widely used in fields such as tower cranes, port handling equipment, and industrial robots, ensuring the stability and reliability of these devices during operation.

Define the Working Conditions of slewing bearing

Magnitude and Direction，Accurately measure the magnitude of the load borne by the bearing and distinguish whether it is a radial load, an axial load, or a combination of both. For example, the spindle of a machine tool mainly bears radial cutting forces, while the wheel hub bearing of a car has to withstand both the radial load caused by the vehicle’s weight and the axial force generated during vehicle steering. Select a suitable flange bearing according to the load characteristics. For instance, deep – groove ball flange bearings can withstand certain radial and axial loads, and tapered roller flange bearings are better at withstanding larger axial and radial forces.

Nature，Determine whether the load is stable or impact – type. In the metallurgical industry, for example, the frequent handling of heavy objects subjects the flange bearings of cranes to impact loads. In such cases, self – aligning roller flange bearings that can withstand impacts should be selected. Their structure can buffer the impacts and prevent premature damage to the bearings.

Operating Speed，Select the appropriate flange bearing based on the operating speed of the equipment. For high – speed rotating equipment such as motors, the bearing is required to have a low friction coefficient and a high limiting speed. Ceramic ball flange bearings can be used. The low – friction characteristics of ceramic materials help reduce heat generation and meet the requirements of high – speed operation. For low – speed and heavy – load machinery, such as crushers in mining machinery, more attention is paid to the bearing’s load – bearing capacity, and the requirement for speed is relatively low. Spherical roller flange bearings are a good choice as they can withstand heavy loads at low speeds.

Operating Temperature，Consider the temperature range of the bearing’s working environment. In high – temperature environments, ordinary carbon steel flange bearings are prone to deformation and a decrease in hardness. High – temperature – resistant alloy – material flange bearings, such as those containing alloying elements like chromium and molybdenum, should be selected. These bearings can maintain good mechanical properties at high temperatures. In low – temperature environments, to avoid embrittlement of the bearing material, flange bearings made of special low – temperature steel should be chosen to ensure sufficient toughness and strength at low temperatures.

Consider the Equipment Requirements

Installation Space，Measure the dimensions of the installation space reserved in the equipment, including the inner diameter, outer diameter, and thickness of the bearing housing. If the installation space is limited, flange bearings with a compact outer dimension, such as thin – type flange bearings, should be selected. Their thin – type design can achieve good support and rotation functions in a narrow space. If the space is relatively sufficient, bearings of more suitable sizes can be selected according to load and speed conditions.

Accuracy Requirements，Select the bearing accuracy grade according to the equipment’s requirements for motion accuracy. Precision machine tools have extremely high requirements for processing accuracy and need to use high – precision P4 or P5 – grade flange bearings to ensure the dimensional accuracy and surface quality of the processed parts. For ordinary machinery with low accuracy requirements, such as agricultural machinery, ordinary – accuracy – grade (e.g., P0) flange bearings can meet the usage requirements.

Sealing Requirements，Analyze whether there are dust, moisture, corrosive media, etc., in the equipment’s working environment. In a dusty mining environment, to prevent dust from entering the bearing and aggravating wear, flange bearings with a sealing device, such as rubber – sealed flange bearings, should be selected. Their sealing structure can effectively block dust. In a humid or corrosive – medium environment, such as in chemical equipment, in addition to selecting sealed bearings, the corrosion resistance of the bearing material also needs to be considered. Stainless – steel flange bearings can be selected.

Understand the Bearing Characteristics

Structural Types，Familiarize yourself with the characteristics of different structural flange bearings. For example, flanged mounted bearings are easy to install and can be directly fixed on the equipment’s installation surface. Flanged spherical plain bearings have an automatic self – aligning function and can compensate for misalignment caused by installation errors or shaft deflection. Flange ball bearings have a low friction coefficient and high rotational speed, and flange roller bearings have a large load – bearing capacity. Select a bearing with a matching structure according to the actual needs of the equipment.

Material Characteristics，Understand the performance of commonly used bearing materials. Bearing steel is the most common material, with high hardness, high strength, and good wear resistance. Stainless – steel flange bearings have strong corrosion resistance. Ceramic – material bearings have characteristics such as low density, high hardness, high temperature resistance, and insulation. Select the appropriate bearing material according to the working conditions and equipment requirements.

Lubrication Methods，Different lubrication methods have a significant impact on the performance of flange bearings. Grease lubrication is simple to operate and convenient to maintain, and is suitable for medium – and low – speed, light – load, and occasions where it is not convenient to refuel frequently. Oil lubrication has good heat dissipation performance and can effectively reduce friction, and is often used in high – speed and heavy – load equipment. Determine the appropriate lubrication method according to the working conditions and requirements of the equipment, and select a flange bearing that matches it.

Prices of Flange Slewing bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High – quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is also high. Secondly, slewing bearings with complex manufacturing processes and high – precision requirements need advanced equipment and strict quality control, and the price will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and the amount of materials used, and the higher the price will be.

Suppliers of Flange Slewing bearings

With excellent product quality, strong technical strength, and a perfect service system, ldb bearing company has become a benchmark in the slewing bearing industry. In the future, it is believed that it will continue to adhere to the concept of innovation and quality first, shine more brightly in the global market, and contribute more to the development of various industries.

Influence of the Number of Balls on the Performance of Slewing bearings

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Slewing bearings, as crucial components in the mechanical field, are widely used in equipment such as cranes, excavators, and tunnel boring machines. Their performance is restricted by many factors, and the number of balls is one of the important influencing factors, playing a key role in load – bearing capacity, slewing accuracy, friction characteristics, service life, and other aspects.

What is Double – Row Ball Slewing bearing?

The double – row ball slewing bearing is a mechanical component used to achieve the slewing motion of components. It mainly consists of an inner ring, an outer ring, two rows of steel balls with the same diameter, and a cage. The two rows of steel balls are evenly distributed between the inner and outer rings and jointly bear axial forces, radial forces, and overturning moments. Relative slewing is achieved through the contact and rolling of the steel balls and the raceways. It has a simple structure, is easy to install, can withstand complex loads to a certain extent, and is often used in equipment such as small cranes, aerial work platforms, and small wind turbines that do not require particularly high slewing accuracy but need to bear certain axial and radial forces.

What is Four – Point Contact Slewing bearing?

The four – point contact slewing bearing is a type of slewing bearing. It is composed of an inner ring, an outer ring, steel balls, and a cage. Its uniqueness lies in that each steel ball has four – point contact with the raceways of the inner and outer rings. This structure enables it to simultaneously bear large axial forces, radial forces, and overturning moments. During operation, the four – point contact can effectively disperse the load and reduce local stress concentration. It is often used in equipment with compact space requirements and the need to bear multiple types of loads, such as tower cranes and port cranes. Compared with other slewing bearings, the four – point contact slewing bearing has a compact structure, occupies less space, and can provide reliable slewing motion and stable load – bearing performance in a limited space.

Load – Bearing Capacity of Slewing bearings

Increasing the number of balls can enhance the load – bearing capacity of slewing bearings. In a double – row ball slewing bearing, the steel balls are evenly distributed to bear axial forces, radial forces, and overturning moments. More steel balls mean a larger load – bearing area and a more uniform load distribution, which can share the force on a single steel ball. Taking a port crane as an example, when the number of balls in the slewing bearing increases, it can effectively disperse the huge forces generated when lifting heavy objects, prevent excessive wear or deformation of the steel balls, thereby enhancing the overall load – bearing capacity of the support and ensuring the safe and efficient operation of the equipment. However, the number of balls is not the more the better. Excessive balls will increase the contact stress between them, leading to increased friction and energy consumption, and instead reducing the load – bearing efficiency.

Slewing Accuracy of Slewing bearings

Slewing accuracy is an important performance indicator of slewing bearings. Appropriately increasing the number of balls helps to improve slewing accuracy. More steel balls make the load distribution more uniform, reducing eccentricity and shaking caused by uneven loads. For example, in the slewing bearing of a precision radar device, by increasing the number of steel balls, the load fluctuation borne by a single steel ball is reduced, making the radar more stable during rotation, with a smaller angular error, and ensuring its accurate tracking of targets. However, too many balls will increase the manufacturing and installation difficulties. Once there are deviations in the size or installation accuracy of the steel balls, it will instead damage the slewing accuracy and cause the equipment to operate unstably.

Friction Characteristics of Slewing bearings

The change in the number of balls has a significant impact on the friction characteristics of slewing bearings. As the number of balls increases, the contact area increases, and the friction resistance will also increase accordingly. In some equipment with high requirements for slewing flexibility, too many steel balls will cause difficult rotation and increased energy consumption. For example, in an aerial work platform, if the number of balls in the slewing bearing is too large, the operator will feel obvious jamming when turning the platform, increasing the operation difficulty and energy consumption. Conversely, if the number of balls is too small, the pressure on a single steel ball is high, and the wear will be accelerated, which will also affect the smoothness of slewing. Therefore, it is necessary to select the appropriate number of balls according to the equipment working conditions to balance the friction resistance and load – bearing capacity and ensure the normal operation of the equipment.

Service Life of Slewing bearings

The number of balls is closely related to the service life of slewing bearings. Reasonably increasing the number of balls can extend the service life. When the number of balls is sufficient, the load borne by a single ball is relatively reduced, and the degree of wear is reduced, which can effectively reduce the occurrence of fatigue wear and plastic deformation. Taking the slewing bearing of a wind turbine as an example, more steel balls can better bear the complex loads generated by the rotation of the blades, reduce the wear of the steel balls and raceways, extend the service life of the slewing bearing, and reduce the maintenance cost. However, if the number of balls exceeds the reasonable range, due to increased friction and heat generation, it will accelerate the aging and fatigue of the material and shorten the service life.

When designing and selecting slewing bearings, it is necessary to comprehensively consider the working conditions and performance requirements of the equipment to determine the number of balls. For heavy – load equipment, such as large – scale mining machinery, it is necessary to increase the number of balls to enhance the load – bearing capacity; for high – precision equipment, such as optical tracking equipment, it is necessary to reasonably increase the number of balls to ensure slewing accuracy. In addition, factors such as material properties, manufacturing processes, and costs also need to be combined to optimize the design of the number of balls while ensuring performance. With the continuous progress of materials science and manufacturing technology, it is expected that breakthroughs will be made in the optimization of the number of balls for slewing bearings in the future. By using new materials and advanced manufacturing processes, the distribution of the number of balls can be made more reasonable, improving performance while reducing costs to meet the higher requirements of different fields for slewing bearings.

Prices of Slewing bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High – quality steel has a high cost and can produce products with excellent performance and long service life, so the price is also high. Secondly, for slewing bearings with complex manufacturing processes and high – precision requirements, advanced equipment and strict quality control are required, which will also increase the price accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and the amount of materials used, and the higher the price will be.

Suppliers of Slewing bearings

The products of ldb bearing company cover a wide range. Whether they are standard – sized or non – standard slewing bearings, the company can produce them with high quality to meet the diverse needs of different customers. In the field of industrial robots, its slewing bearings help the joints of robots achieve high – precision and high – stability rotational motion, making the robot’s movements flexible and precise. In solar power generation equipment, they assist the tracking system in accurately tracking the sun, improving power generation efficiency. The wide application of its products in multiple fields demonstrates its strength.

Differences between Double-row different diameter ball slewing bearing and Double-Row Ball Slewing bearings

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Double-row different diameter ball slewing bearing and double-row ball slewing bearings are two common types of slewing bearings. They have some differences in structure, load-bearing capacity, application scenarios, and other aspects.

What is Double-Row Ball Slewing bearing?

The double-row ball slewing bearing is a mechanical component used to achieve the slewing motion of components. It mainly consists of an inner ring, an outer ring, two rows of steel balls with the same diameter, and a cage. The two rows of steel balls are evenly distributed between the inner and outer rings and jointly bear axial forces, radial forces, and overturning moments. Relative slewing is achieved through the contact and rolling of the steel balls and the raceways. It has a simple structure and is easy to install. It can withstand complex loads to a certain extent and is often used in equipment such as small cranes, aerial work platforms, and small wind turbines that do not require particularly high slewing accuracy but need to bear certain axial and radial forces.

What is Double-row different diameter ball slewing bearing?

The double-row different diameter ball slewing bearing is a slewing bearing device. It is composed of two rows of steel balls with different diameters, inner and outer rings, a cage, and other components. Usually, the diameter of the upper row of steel balls is smaller, mainly bearing axial forces and part of the overturning moment, while the diameter of the lower row of steel balls is larger, mainly bearing radial forces. This structural design can reasonably distribute forces according to different load types and achieve a high load-bearing capacity in a limited space. It has advantages such as good accuracy retention and can adapt to complex working conditions. It is often used in large-scale construction machinery and industrial equipment that require high load-bearing capacity and slewing accuracy, such as large cranes, tunnel boring machines, and large converters.

Structural Characteristics of Slewing bearings

Double-row different diameter ball slewing bearing: The load-bearing rolling elements are composed of two rows of steel balls with different diameters. Generally, the upper row of steel balls with a smaller diameter mainly bears axial forces and part of the overturning moment, and the lower row of steel balls with a larger diameter mainly bears radial forces. This structure can achieve a high load-bearing capacity in a small space by reasonably allocating the diameters and quantities of the steel balls.

Double-Row Ball Slewing bearings: There are two rows of steel balls with the same diameter. The two rows of steel balls are evenly distributed between the inner and outer rings. The two rows of steel balls jointly bear axial forces, radial forces, and overturning moments, and the slewing motion is realized through the contact between the steel balls and the raceways.

Load-Bearing Capacity of Slewing bearings

Double-row different diameter ball slewing bearing: Since steel balls of different diameters are used to bear different types of loads respectively, their load-bearing capacity is highly targeted. For working conditions with large axial forces, radial forces, and overturning moments simultaneously, they can distribute loads more reasonably. Under the same size, they can generally bear a larger overturning moment than double-row ball slewing bearings.

Double-Row Ball Slewing bearings: The two rows of steel balls bear loads evenly and can withstand axial and radial forces well. However, when bearing large overturning moments, due to the same diameter of the steel balls, the load distribution is relatively less reasonable than that of Double-row different diameter ball slewing bearing, and their load-bearing capacity is relatively limited.

Accuracy Retention of Slewing bearings

Double-row different diameter ball slewing bearing: The structural design makes the contact stress distribution between the steel balls and the raceways more uniform when bearing complex loads, which is conducive to reducing the wear and deformation of the raceways. Therefore, it can better maintain slewing accuracy during long-term use.

Double-Row Ball Slewing bearings: They are relatively weak in accuracy retention. Especially when bearing large eccentric loads or impact loads, the wear between the steel balls and the raceways may be aggravated, resulting in a rapid decline in slewing accuracy.

Friction Characteristics of Slewing bearings

Double-row different diameter ball slewing bearing: When the steel balls of different diameters roll, their linear velocities and angular velocities are different, which will generate a certain differential friction. However, through reasonable design and material selection, this differential friction can be controlled within a certain range, and it has little impact on the overall friction characteristics.

Double-Row Ball Slewing bearings: The two rows of steel balls have the same diameter and the same rolling speed. Their friction characteristics are relatively simple, with a small friction resistance, and can provide a relatively smooth slewing motion during low-speed operation.

Installation and Maintenance of Slewing bearings

Double-row different diameter ball slewing bearing: During installation, attention needs to be paid to the installation positions of the upper and lower rows of steel balls and the adjustment of the preload to ensure proper load-bearing and operation. During maintenance, due to the relatively complex structure, it is more difficult to inspect and replace the raceways and steel balls.

Double-Row Ball Slewing bearings: The installation is relatively simple. Only the installation accuracy of the two rows of steel balls and the uniform preload need to be ensured. In terms of maintenance, due to the more intuitive structure, it is relatively easy to inspect and replace components such as steel balls and raceways.

Application Scenarios of Slewing bearings

Double-row different diameter ball slewing bearing: They are often used in large-scale construction machinery that requires high load-bearing capacity and accuracy, such as large cranes and tunnel boring machines, as well as some industrial equipment that needs to operate under complex working conditions, such as port handling equipment and large converters.

Double-Row Ball Slewing bearings: They are suitable for equipment that does not require particularly high slewing accuracy but needs to bear large axial and radial forces, such as small cranes, aerial work platforms, and certain types of wind turbines.

In conclusion, Double-row different diameter ball slewing bearing and double-row ball slewing bearings each have their own characteristics and application ranges. In practical applications, it is necessary to comprehensively consider specific working conditions, equipment requirements, and economic factors to select the appropriate type of slewing bearing to ensure the safe and reliable operation of the equipment and good performance.

Prices of Slewing bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High-quality steel has a high cost and can produce products with excellent performance and long service life, so the price is also high. Secondly, for slewing bearings with complex manufacturing processes and high precision requirements, advanced equipment and strict quality control are required, which will also increase the price accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and the amount of materials used, and the higher the price will be.

Suppliers of Slewing bearings

The products of Ldb bearing company cover a wide range. Advanced production and testing equipment are the cornerstone of high-quality products. Ldb bearing company is well aware of this and is equipped with nearly 30 sets of various types of equipment, from 3m CNC drilling and milling machines to quenching machines, providing hardware support for precision processing. At the same time, the company has an experienced design and technical team. With their profound professional knowledge and innovative spirit, they continuously optimize product designs and overcome technical problems.

Double-row Ball Slewing bearings VS Four-point Contact Slewing bearings

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Double-row ball slewing bearings and four-point contact slewing bearings are two commonly used support structures in the mechanical field. The following are their differences and connections.

What is Double-row Ball Slewing bearing?

The double-row ball slewing bearing is a type of slewing bearing, mainly composed of components such as an inner ring, an outer ring, two rows of steel balls, and spacers. Its unique structure features two rows of steel balls. Compared with single-row ball slewing bearings, this design greatly improves the load-bearing capacity, enabling it to withstand large axial forces, radial forces, and overturning moments simultaneously. It is widely used in various large-scale mechanical equipment, such as port cranes, large excavators, wind power generation equipment, etc. It can ensure the smooth and flexible rotation of key components of the equipment, and is a crucial mechanical component for ensuring the normal operation and efficient operation of these devices. It plays an important role in enhancing the performance and reliability of the equipment.

What is Four-point Contact Slewing bearing?

The four-point contact slewing bearing is a mechanical component composed of an inner ring, an outer ring, rolling elements, etc. The rolling elements have four-point contact with the raceways of the inner and outer rings, and can withstand axial forces, radial forces, and overturning moments simultaneously. It has the characteristics of a compact structure, high rotation accuracy, and large load-bearing capacity, and is widely used in fields such as construction machinery, wind power, and robotics. It can achieve the smooth slewing motion of components and is an essential key component in many large-scale mechanical devices.

Differences of Double-row Ball Slewing bearings and Four-point Contact Slewing bearings

– Structural Features: The double-row ball slewing bearing has three rows of balls. The upper and lower rows are load-bearing balls, and the middle row is spacer balls, which are separated by a cage. The structure is compact and has good rigidity. The four-point contact slewing bearing consists of two raceways, with arc-shaped raceways. The balls have four-point contact with the raceways and can withstand axial forces, radial forces, and overturning moments simultaneously. The structure is relatively simple.

– Load-bearing Capacity: The double-row ball slewing bearing has a large number of evenly distributed balls, which can withstand large axial forces, radial forces, and overturning moments, and is suitable for large-scale mechanical equipment. The balls of the four-point contact slewing bearing have four-point contact with the raceways, and its load-bearing capacity is relatively small, making it suitable for small and medium-sized mechanical equipment.

– Rotational Flexibility: The double-row ball slewing bearing has a large number of balls, resulting in high rolling friction resistance and relatively poor rotational flexibility. The four-point contact slewing bearing has fewer contact points between the balls and the raceways, low rolling friction resistance, and good rotational flexibility.

– Installation Method: The double-row ball slewing bearing is usually fixed to the equipment by bolt connection or welding, and requires high installation accuracy. The installation methods of the four-point contact slewing bearing are more flexible, and can be bolt connection, pin connection, or interference fit. The installation accuracy requirements are relatively low.

– Application Scenarios: The double-row ball slewing bearing is often used in large construction machinery such as large cranes, port machinery, and excavators, as well as in large equipment such as wind turbines and Ferris wheels. The four-point contact slewing bearing is often used in small and medium-sized construction machinery such as small and medium-sized cranes, forklifts, and aerial work platforms, as well as in fields such as industrial robots and automated production lines.

Connections of Double-row Ball Slewing bearings and Four-point Contact Slewing bearings

– Functional Role: Both double-row ball slewing bearings and four-point contact slewing bearings are used to achieve the slewing motion of mechanical equipment, support the weight and load of the equipment, and enable the equipment to rotate flexibly within a certain angle range.

– Working Principle: Both are based on the principle of rolling friction. The slewing motion is achieved through the rolling of the balls in the raceways, reducing the friction resistance and improving the rotation efficiency.

– Materials and Manufacturing Processes: The materials used to manufacture double-row ball slewing bearings and four-point contact slewing bearings are usually high-strength alloy steels, which are processed through multiple processes such as forging, heat treatment, and machining to ensure good strength, hardness, and wear resistance.

– Maintenance: During the use process, both double-row ball slewing bearings and four-point contact slewing bearings need to be regularly maintained, including cleaning, lubrication, and inspection of the wear of the balls and raceways, etc., to extend their service life and ensure the normal operation of the equipment.

Double-row ball slewing bearings and four-point contact slewing bearings have certain differences in structural features, load-bearing capacity, rotational flexibility, installation methods, and application scenarios. However, they have many similarities in functional roles, working principles, materials and manufacturing processes, and maintenance. In practical applications, it is necessary to select the appropriate type of slewing bearing according to specific equipment requirements and working conditions.

Prices of Slewing bearings

There are many factors that affect the price of slewing bearings. Firstly, the raw materials matter. High-quality steel has a high cost, and products made from it have excellent performance and a long service life, thus having a higher price. Secondly, slewing bearings with complex manufacturing processes and high precision requirements require advanced equipment and strict quality control, which will also increase the price accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price will be.

Supplier of Slewing bearings

In terms of quality, ldb bearing company has achieved excellence. Every link from the incoming inspection of raw materials to the delivery of finished products is strictly controlled. Multidimensional inspections are carried out on raw materials to ensure that their quality meets the standards. During the production process, each processing procedure is strictly supervised, and detailed records are kept. With its excellent product quality, strong technical strength, and complete service system, ldb bearing company has become a benchmark in the slewing bearing industry. In the future, it is believed that it will continue to uphold the concept of innovation and quality first, shine more brightly in the global market, and contribute more to the development of various industries.

How to Maintain Double-row Ball Slewing bearings

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Double-row ball slewing bearings play a crucial role in many large-scale mechanical equipment. Their operating conditions are directly related to the stability and service life of the equipment. Maintain them well can not only extend their service life but also ensure the efficient and safe operation of the equipment.

What is Double-row Ball Slewing bearing?

A double-row ball slewing bearing is a type of slewing bearing, mainly composed of inner rings, outer rings, two rows of steel balls, and spacers. Its unique structure features two rows of steel balls. Compared with single-row ball slewing bearings, this design greatly improves the load-carrying capacity and can simultaneously withstand large axial forces, radial forces, and overturning moments. It is widely used in various large-scale mechanical equipment, such as port cranes, large excavators, and wind power generation equipment. It can ensure the smooth and flexible rotation of key components of the equipment and is a key mechanical component to ensure the normal operation and efficient operation of these equipment, playing an important role in enhancing the performance and reliability of the equipment.

Methods for Maintaining Double-row Ball Slewing Rings

Daily inspection is the basic work of maintaining double-row ball slewing bearings. Before and after each use of the equipment, a detailed inspection of the slewing bearing should be carried out. Check whether there are obvious cracks, scratches, or deformations on the surface of the slewing bearing. If cracks are found, even slight ones, they may gradually expand during the operation of the equipment and eventually lead to the failure of the slewing bearing. It must be replaced in a timely manner. Scratches will damage the surface accuracy of the slewing bearing and accelerate wear. It is necessary to evaluate its severity and decide whether to repair or replace it. At the same time, check whether the connecting bolts of the slewing bearing are loose. Loose bolts will cause additional vibration and displacement during the operation of the slewing bearing, affecting the equipment accuracy and even causing safety accidents. Once loose bolts are found, they should be tightened according to the specified torque immediately. In addition, pay attention to observing the sealing condition of the slewing bearing. Check whether the seals are damaged or aged. If there are any problems, replace the seals in a timely manner to prevent dust, impurities, and moisture from invading and avoid wearing and corroding the rolling elements and raceways.

Lubrication is the core link in maintaining double-row ball slewing bearings. During the operation of the slewing bearing, there is relative motion between the rolling elements and the raceways. Good lubrication can effectively reduce the friction coefficient, reduce wear, and extend the service life. Select appropriate lubricants according to the working environment and requirements of the slewing bearing. Under general working conditions, lithium-based grease can be selected; in high-temperature environments, high-temperature-resistant grease should be used; in environments with a risk of chemical corrosion, lubricants with anti-corrosion properties are required. The frequency of lubrication is also crucial. Excessive lubrication will cause waste of lubricants, increase costs, and may also adsorb more dust; untimely lubrication will lead to increased wear of components. Usually, after the equipment has been in operation for a certain period of time or worked for a certain number of hours, supplementary lubrication should be carried out. For example, for continuously operating equipment, lubrication should be carried out at least once a week; for intermittently used equipment, the lubrication cycle can be determined according to the actual working hours. When adding lubricants, ensure that the lubricants are evenly applied to the surfaces of the rolling elements and raceways. You can inject oil through a special oil injection nozzle until new lubricants are extruded from the seal to ensure sufficient lubrication.

Regular cleaning of double-row ball slewing bearings is also essential. During the operation of the equipment, the slewing bearing will adsorb a large amount of dust and impurities. If these substances are not cleaned in a timely manner, they will enter the interior of the slewing bearing and accelerate wear. When cleaning, first cut off the power supply of the equipment to ensure operation safety. Then, use a clean cloth or brush to gently wipe the dust and dirt on the surface of the slewing bearing. For stubborn oil stains and impurities, an appropriate amount of cleaning agent can be used, but pay attention to choosing a cleaning agent that has no corrosive effect on the slewing bearing. After cleaning, rinse with clean water and dry the surface moisture to prevent the remaining cleaning agent from corroding the slewing bearing. At the same time, also clean the environment around the slewing bearing, keep the area around the equipment clean, and reduce the source of dust and impurities.

Regularly detecting and adjusting the accuracy of double-row ball slewing bearings can ensure the normal operation accuracy of the equipment. With the use of the equipment, accuracy problems such as radial runout, axial runout, and end face runout may occur in the slewing bearing. Professional detection tools such as dial indicators can be used to regularly detect the accuracy of the slewing bearing. If the accuracy is found to exceed the specified range, adjustments should be made in a timely manner. During the adjustment, corresponding measures should be taken according to specific accuracy problems. For example, for excessive radial runout, the bearing clearance can be adjusted to solve it; for axial runout problems, it may be necessary to adjust the installation position of the slewing bearing or replace relevant components. During the adjustment process, strictly follow the equipment operation manual to ensure the accuracy and safety of the adjustment.

Storage maintenance is also an important part of the maintenance of double-row ball slewing bearings. If the equipment is not used for a long time, the slewing bearing needs to be properly stored. First, clean the surface of the slewing bearing and apply a layer of anti-rust oil to prevent rust. Then, place the slewing bearing in a dry and well-ventilated warehouse to avoid getting damp and rained on. When storing, avoid subjecting the slewing bearing to heavy pressure or collisions to prevent deformation. For large slewing bearings, special brackets can be used for storage to ensure their stable state. At the same time, regularly check the stored slewing bearings to see if the anti-rust oil has fallen off and if there are signs of rust on the surface. If there are any problems, deal with them in a timely manner.

Maintaining double-row ball slewing bearings is a systematic and meticulous task, covering many aspects such as daily inspection, lubrication, cleaning, accuracy detection and adjustment, and storage maintenance. Only by doing a good job in the maintenance of each link can the double-row ball slewing bearing always be in a good operating state, providing strong support for the stable operation of the equipment, reducing the equipment maintenance cost, and improving production efficiency.

The Price of Double-row Ball Slewing bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials: high-quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is high. Secondly, slewing bearings with complex manufacturing processes and high precision requirements require advanced equipment and strict quality control, and their prices will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price.

Suppliers of Double-row Ball Slewing bearings

In terms of services, ldb bearing Company is also remarkable. Before sales, it provides professional selection suggestions according to customers’ needs and can also customize products or upgrade the existing slewing structures of main engines. During sales, it strictly controls the production progress and quality to ensure the on-time and high-quality delivery of products.With excellent product quality, strong technical strength, and a perfect service system, ldbbearing Company has become a benchmark in the slewing bearing industry. In the future, it is believed that it will continue to uphold the concept of innovation and quality first and shine more brightly in the global market, contributing more to the development of various industries.

How to Select a Double Row Ball Slewing Bearing

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In the operation of numerous mechanical devices, the double row ball slewing bearing plays a crucial role, directly influencing the performance, stability, and service life of the equipment. To choose a suitable double row ball slewing bearing, it is necessary to comprehensively consider multiple factors.

What is Double Row Ball Slewing Bearing?

The double row ball slewing bearing is a type of slewing bearing, mainly composed of components such as an inner ring, an outer ring, two rows of steel balls, and spacers. Its unique structure features two rows of steel balls. Compared with single row ball slewing bearings, this design significantly enhances the load – carrying capacity, enabling it to simultaneously withstand large axial forces, radial forces, and overturning moments. It is widely used in various large – scale mechanical equipment, such as port cranes, large – scale excavators, and wind power generation equipment. It can ensure the smooth and flexible rotation of key components of the equipment, and is a key mechanical component for ensuring the normal operation and efficient operation of these devices. It plays an important role in enhancing the performance and reliability of the equipment.

Key Factors in Selecting a Slewing Bearing

The double row ball slewing bearing needs to withstand axial forces, radial forces, and overturning moments. It is necessary to accurately calculate various loads generated during the operation of the equipment and determine the load – carrying capacity requirements of the slewing bearing according to the actual working conditions. For example, when a large – scale crane is lifting heavy objects, the slewing bearing not only has to bear the gravity of the heavy objects (radial force), but also has to cope with the overturning moment generated by the rotation of the boom. If the load – carrying capacity is insufficient, the slewing bearing is prone to premature wear, deformation, or even failure. Excessive load – carrying capacity will increase costs and cause waste of resources. When calculating, relevant formulas in mechanical design manuals can be referred to, and accurate calculations can be carried out by combining parameters such as the equipment’s working class, maximum lifting capacity, and slewing radius.

Accuracy is equally important. Different devices have significantly different accuracy requirements for slewing bearings. Equipment such as precision machine tools and robots require slewing bearings to have extremely high rotational accuracy to ensure the accuracy of processing or operation. For some ordinary construction machinery with relatively low accuracy requirements, such as small loaders, the accuracy requirements are not so strict. The accuracy of slewing bearings mainly includes indicators such as radial run – out, axial run – out, and end – face run – out. When selecting, it is necessary to choose products that meet the corresponding accuracy levels according to the accuracy requirements of the equipment. Generally, the higher the accuracy level, the higher the price. Therefore, it is necessary to reasonably select the accuracy level on the premise of meeting the equipment’s usage requirements.

Speed limits also need to be carefully considered. Each double row ball slewing bearing has its allowable maximum speed. If the actual working speed of the equipment exceeds the limit speed of the slewing bearing, it will lead to increased friction and severe heat generation, thus shortening the service life of the slewing bearing and even causing malfunctions. When selecting, it is necessary to clarify the normal working speed range of the equipment and ensure that the maximum speed of the selected slewing bearing is greater than the working speed of the equipment. At the same time, the impact of speed changes on the slewing bearing, such as the impact during start – up and shutdown, also needs to be considered. For working conditions with high speeds, slewing bearings with good lubrication performance and lightweight rolling elements can be selected.

The size specification is the basis for selection. It is necessary to determine the outer dimensions of the slewing bearing, including the outer diameter, inner diameter, and width, according to the structure and installation space of the equipment. At the same time, details such as the position, size, and number of installation holes also need to be considered to ensure that the slewing bearing can be perfectly adapted to the equipment. If the size is too large or too small, it cannot be installed and used normally. In the design stage, sufficient installation space for the slewing bearing should be fully considered and reserved. When selecting, the size parameters of the product should be carefully checked to avoid installation problems.

The sealing and lubrication conditions are directly related to the service life of the slewing bearing. Good sealing can effectively prevent the intrusion of dust, impurities, and moisture, avoiding the wear and corrosion of the rolling elements and raceways. Common sealing methods include rubber seals and labyrinth seals. The appropriate sealing form should be selected according to the working environment of the equipment. In dusty and humid environments, rubber seals with good sealing performance should be selected and regularly inspected and replaced. In clean and dry environments, labyrinth seals may be sufficient to meet the requirements. In terms of lubrication, it is necessary to ensure that the slewing bearing is well – lubricated to reduce friction and wear. Different types of slewing bearings have different requirements for lubricants. Appropriate lubricants should be selected according to the product instructions and added or replaced regularly.

The material quality determines the performance and reliability of the slewing bearing. Common materials for slewing bearings include high – quality carbon steel and alloy steel. High – quality materials have characteristics such as high strength, high hardness, good wear resistance, and corrosion resistance. When selecting, attention should be paid to the quality of the materials and the heat treatment process. Materials subjected to appropriate heat treatment can further improve their comprehensive performance. For slewing bearings used in harsh working conditions, such as high – temperature, heavy – load, and strong – corrosion environments, special materials or products with surface treatment, such as carburized and quenched alloy steel, should be selected to improve their performance and service life.

The manufacturing process affects the quality and accuracy of the slewing bearing. Advanced manufacturing processes can ensure the dimensional accuracy, surface quality, and assembly quality of the slewing bearing. When selecting, it is necessary to understand the manufacturing process level of the manufacturer, such as the advancement of processing equipment, the standardization of the production process, and the perfection of the quality control system. The manufacturing process can be evaluated by visiting the manufacturer, checking product samples, and understanding user reviews. Products processed by numerical control machine tools, assembled automatically, and strictly quality – tested are more reliable in quality and more stable in performance.

The Price of Double Row Ball Slewing Bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High – quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is also high. Secondly, slewing bearings with complex manufacturing processes and high – precision requirements require advanced equipment and strict quality control, so the price will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price. Brands and manufacturers’ reputations are also crucial. Well – known brands invest a lot in research and development, production, and after – sales service. Their products are of reliable quality, and the prices are also on the high side. Finally, the market supply – and – demand relationship affects the price. When the demand is strong and the supply is tight, the price rises; otherwise, it falls.

Suppliers of Double Row Ball Slewing Bearings

In terms of quality control, ldb bearing company does an excellent job. Every link from the incoming of raw materials to the outgoing of finished products is strictly controlled. Raw materials are multi – dimensionally tested to ensure their quality compliance. During the production process, every processing step is strictly inspected, and detailed records are kept. Before the finished products leave the factory, comprehensive performance tests are carried out, and only products that fully meet the standards can enter the market.

The Development History of Four-Point Contact Slewing Bearings

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The development history of four-point contact slewing bearings is a history of continuous innovation and breakthroughs. It has always kept pace with the development of science and technology and continuously met the growing demands of various industries for mechanical components.

What is Four-Point Contact Slewing Bearing?

The four-point contact slewing bearing is a mechanical component composed of an inner ring, an outer ring, rolling elements, etc. The rolling elements have four-point contact with the raceways of the inner and outer rings, enabling the bearing to withstand axial forces, radial forces, and overturning moments simultaneously. It features a compact structure, high rotational accuracy, and large load-carrying capacity. It is widely used in fields such as construction machinery, wind power, and robotics, and can realize the smooth rotational movement of components. It is an indispensable key component in many large-scale mechanical equipment.

The Impetus of the Industrial Revolution: The Germination of Modern Slewing Bearings

It was the Industrial Revolution in the 18th century that truly promoted the development of slewing bearings. The widespread application of industrial manufacturing and mechanical devices put forward higher requirements for bearing technology. In 1776, the gyroscopic disc-shaped rolling bearing invented by the Scottish engineer John Sgriam was regarded as the prototype of modern slewing bearings. In the early 19th century, the British engineer Robert Jenner further improved the design and invented a metal bearing, making the slewing movement more stable and reliable and promoting the widespread application of slewing bearings in industrial machinery and railway transportation.

The Key Breakthrough in the Early 20th Century: The Birth of Four-Point Contact Slewing Bearings

The early 20th century was an important stage in the development of four-point contact slewing bearings. In 1912, the spherical ball device invented by the British engineer Joseph Thomson laid the foundation for the design of four-point contact slewing bearings. This design enables the bearing to withstand axial loads, radial loads, and tilting moments through the four-point contact between the steel balls and the bearing raceways, greatly expanding the application range of slewing bearings. Since then, four-point contact slewing bearings have continuously improved in design and manufacturing technology. The application of new materials and new technologies has significantly improved their load capacity, wear resistance, and service life.

The Leap in the Mid-20th Century: Material and Process Innovation

In the mid-20th century, with the rapid development of materials science and manufacturing processes, four-point contact slewing bearings迎来了新的突破. The application of new materials such as high-strength alloy steel and ceramic materials has significantly enhanced the performance of slewing bearings. High-strength alloy steel improves the load-carrying capacity and wear resistance of slewing bearings, while ceramic materials endow them with the characteristics of high temperature resistance, corrosion resistance, and low friction, enabling them to operate stably under harsher working conditions. At the same time, the improvement of manufacturing processes, such as the development of precision machining technology and heat treatment technology, has further improved the accuracy and reliability of slewing bearings.

During this period, four-point contact slewing bearings were widely used in fields such as construction machinery, construction machinery, metallurgical machinery, and ship machinery. In construction machinery, such as excavators and cranes, four-point contact slewing bearings enable the working devices to rotate flexibly and efficiently complete various operation tasks; in construction machinery, the slewing mechanism of tower cranes relies on four-point contact slewing bearings to achieve the precise lifting of heavy objects; in metallurgical machinery, the slewing bearings used in equipment such as converters and continuous casters need to withstand huge loads and harsh working environments, and four-point contact slewing bearings ensure the stable operation of the equipment with their excellent performance; in ship machinery, four-point contact slewing bearings provide reliable slewing support for equipment such as ship rudders and cranes.

Modern Innovation and Development: Technology-Driven and Application Expansion

With the continuous progress of science and technology, four-point contact slewing bearings have been continuously innovating in design and manufacturing. The application of technologies such as computer-aided design (CAD) and computer-aided engineering (CAE) enables engineers to design and analyze the structure and performance of slewing bearings more accurately, optimize design schemes, and improve product quality. At the same time, advanced manufacturing equipment and processes, such as numerical control machine tool processing and automated production lines, ensure the high-precision manufacturing and stable production of slewing bearings.

In the application field, four-point contact slewing bearings are constantly expanding new markets. In the wind power generation field, with the growing global demand for clean energy, the installed capacity and single-unit power of wind turbines are constantly increasing, putting forward higher requirements for the load-carrying capacity, reliability, and service life of slewing bearings. Four-point contact slewing bearings have become key components of the yaw and pitch systems of wind turbines with their good performance. In the industrial robot field, with the rapid development of intelligent manufacturing, industrial robots are being used more and more widely. Four-point contact slewing bearings provide high-precision and high-reliability slewing support for the joints of industrial robots, enabling robots to achieve more flexible and precise movements.

The Price of Four-Point Contact Slewing Bearings

There are many factors affecting the price of slewing bearings. Firstly, raw materials. High-quality steel has a high cost, and products made from it have excellent performance and a long service life, so the price is also high. Secondly, slewing bearings with complex manufacturing processes and high precision requirements require advanced equipment and strict quality control, so the price will also increase accordingly. Moreover, the larger and more special the size and specifications are, the greater the processing difficulty and material consumption, and the higher the price.

Suppliers of Four-Point Contact Slewing Bearings

In the field of slewing bearings, ldb bearing company shines globally with its excellent quality and innovation capabilities. With its profound heritage and unremitting efforts, the products of ldb bearing company cover a wide range. Whether they are standard or non-standard slewing bearings, they can be manufactured with high quality to meet the diverse needs of different customers. Advanced production and testing equipment are the cornerstone of high-quality products. ldb bearing company is well aware of this and is equipped with nearly 30 sets of various types of equipment. The company has an experienced design and technical team. With their profound professional knowledge and innovative spirit, they continuously optimize product designs and overcome technical problems.

The Influence of Different Radii on the Performance of Slewing Bearings

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Slewing bearings play a crucial role in numerous mechanical fields. Changes in the radius of a slewing bearing can significantly affect its performance. In different industrial scenarios, the rational selection of the slewing bearing radius is of great importance for the efficient operation, safety, and stability of equipment.

What are Slewing Bearings with Different Radii?

The radius of a slewing bearing has multiple impacts on its performance. In practical applications, factors such as the specific working conditions of the equipment, load-carrying requirements, accuracy requirements, and cost budget need to be comprehensively considered to select a suitable slewing bearing radius. With the continuous progress of science and technology, in the future design and manufacturing of slewing bearings, more attention will be paid to optimizing the matching between the radius and other parameters to further improve the performance of slewing bearings and meet the growing demands of different fields.

Load-Carrying Capacity of Slewing Bearings with Different Radii

The radius of a slewing bearing is closely related to its load-carrying capacity. From the perspective of mechanical principles, slewing bearings with a larger radius have advantages in withstanding axial forces, radial forces, and overturning moments. Take a large crane as an example. Its slewing bearing needs to bear the huge gravity of the boom and the heavy object (generating an axial force), the swing during the hoisting process (generating a radial force), and the overturning moment caused by the eccentricity of the heavy object. When the radius of the slewing bearing increases, the contact area between the raceway and the rolling elements also increases. According to the pressure formula P=\frac{F}{S} (where P is pressure, F is force, and S is the stressed area), under the same load, the increase in the contact area reduces the pressure per unit area. This means that a slewing bearing with a larger radius can more effectively distribute the load without increasing the material strength, thereby improving the load-carrying capacity. Generally, under the same other conditions, if the radius of the slewing bearing is doubled, its load-carrying capacity may increase several times or even more. The specific increase depends on the structural design and material properties of the slewing bearing.

Rotational Accuracy of Slewing Bearings with Different Radii

Rotational accuracy is one of the important indicators for measuring the performance of a slewing bearing, and the radius also has a significant impact on it. When a slewing bearing with a smaller radius is in operation, due to the relatively large influence of the contact accuracy between the rolling elements and the raceway and manufacturing errors, it is prone to generating large rotational errors. However, for a slewing bearing with a larger radius, under the same manufacturing accuracy, the relative error will be reduced. For example, on the turntable of a precision optical instrument, if the radius of the slewing bearing is too small, even if the manufacturing accuracy of the rolling elements and the raceway is very high, small errors may still cause the turntable to shake significantly during rotation, affecting the measurement accuracy of the optical instrument. On the contrary, a slewing bearing with a larger radius can provide a more stable rotational motion, reducing shaking and eccentricity, thereby improving rotational accuracy. Usually, high-precision large slewing bearings, such as those used in astronomical telescopes, have a large radius, and the rotational accuracy can be controlled within a very small range, meeting the requirements of high-precision observations.

Stability of Slewing Bearings with Different Radii

The stability of a slewing bearing is crucial for the safe operation of equipment. Changes in the radius directly affect the stability of the slewing bearing. Slewing bearings with a larger radius usually have a lower center of gravity, which helps to improve the stability of the equipment during operation. Take a wind turbine as an example. Its slewing bearing has a large radius. Under the action of strong winds, the large radius enables the overturning moment generated by the wind to be more effectively dispersed and resisted, reducing the risk of the wind turbine toppling. In addition, slewing bearings with a larger radius also perform better in resisting external impacts and vibrations. When the equipment is disturbed by the outside world, a slewing bearing with a larger radius can, by virtue of its large inertia and structural strength, better maintain stable operation and reduce the possibility of vibration being transmitted to other components of the equipment. However, slewing bearings with a smaller radius, due to their higher center of gravity and relatively compact structure, are more likely to shake and become unstable when facing large external forces.

Friction Resistance of Slewing Bearings with Different Radii

The radius also has a certain impact on the friction resistance of a slewing bearing. During the operation of a slewing bearing, friction resistance is generated between the rolling elements and the raceway. Generally, for slewing bearings with a larger radius, the movement trajectory of the rolling elements is longer. Under the same load and lubrication conditions, the friction resistance will be relatively large. However, with the development of materials science and lubrication technology, the friction resistance can be effectively reduced by using materials with a low friction coefficient and efficient lubrication methods. For example, in the slewing bearings of some large port cranes, although the radius is large, the friction resistance is well controlled through the use of special anti-friction materials and advanced lubrication systems. At the same time, slewing bearings with a larger radius have an advantage in heat dissipation and can better dissipate the heat generated by friction, avoiding problems such as lubrication failure and increased component wear caused by excessive temperature.

Installation Space and Cost of Slewing Bearings with Different Radii

The selection of the slewing bearing radius also needs to consider installation space and cost factors. Slewing bearings with a larger radius usually require more installation space, which may be a limiting factor in some equipment with limited space. For example, in the joints of some small industrial robots, due to the narrow space, only slewing bearings with a smaller radius can be selected. In addition, slewing bearings with a larger radius have higher costs in terms of material usage and manufacturing processes. Manufacturing large slewing bearings requires larger specifications of raw materials and is more difficult to process, thus increasing the manufacturing cost. Therefore, when selecting the slewing bearing radius, factors such as the actual needs of the equipment, installation space, and cost budget need to be comprehensively considered.

Price of Slewing Bearings with Different Radii

The prices of slewing bearings with different radii are affected by multiple factors. In terms of radius size, large-radius slewing bearings are more expensive due to more material usage and difficult processing. Regarding materials, the costs of high-quality alloy steel, stainless steel, etc. vary, which affects the price. The accuracy grade is crucial. High-precision slewing bearings require advanced equipment and strict quality control, and the high cost leads to a high price. Different load-carrying capacities mean that thick plates and large balls are used to meet high-load requirements, which will increase the price. Surface treatments such as chrome plating and other processes increase costs and also cause price differences.

Supplier of Slewing Bearings with Different Radii

Since its establishment, ldb bearing Company has always shone with a unique luster. It is rooted in Luoyang, Henan Province, a fertile ground for the bearing industry. With its professional design and R & D capabilities, it has created many products of excellent quality. The company’s product specifications are rich and diverse. Whether they are standard products or non-standard products, they all demonstrate exquisite craftsmanship. From the entry of raw materials into the factory to the output of finished products, strict process control and quality management are implemented at every step.